Hello Fabiano,
On Wed, 5 Mar 2025 at 19:26, Fabiano Rosas <faro...@suse.de> wrote:
> Note that none of this is out of the ordinary, you'll find such
> discussions in any thread on this community. It may feel arbitrary to
> you because that's tacit knowledge we gathered along the years.
* I understand. I don't find it arbitrary.
> We need an extra patch that reads:
>
> migration: Refactor channel discovery mechanism
>
> The various logical migration channels don't have a standardized way of
> advertising themselves and their connections may be seen out of order
> by the migration destination. When a new connection arrives, the
> incoming migration currently make use of heuristics to determine which
> channel it belongs to.
>
> The next few patches will need to change how the multifd and postcopy
> capabilities interact and that affects the channel discovery heuristic.
>
> Refactor the channel discovery heuristic to make it less opaque and
> simplify the subsequent patches.
>
> <some description of the new code which might be pertinent>
> ---
>
> You'd move all of the channel discovery code into this patch. Some of it
> will be unreacheable because multifd is not yet allowed with postcopy,
> but that's fine. You can mention it on the commit message.
Please see:
->
https://privatebin.net/?dad6f052dd986f9f#FULnfrCV29NkQpvsQyvWuU4HdYjDwFbUPbDtvLro7mwi
* Does this division look okay?
> About moving the code out of migration.c, it was a suggestion that
> you're free to push back. Ideally, doing the work would be faster than
> arguing against it on the mailing list. But that's fine.
* Same here, I'm not against moving that code part to connection.c OR
doing the work. My suggestion has been to do that movement in another
series and not try to do everything in this one series.
> About the hang in the test. It doesn't reproduce often, but once it
> does, it hangs forever (although I haven't waited that long).
* Okay, I'm not seeing it or able to reproduce it across 3 different
machines. One is my laptop and the other 2 are servers wherein I'm
testing migrations of guests with 64G/128G of RAM and guest dirtying
memory to the tune of 68M/128M/256M bytes. I'll keep an eye on it if I
find something.
Thank you.
---
- Prasad
